Fan motor structure

ABSTRACT

Disclosed herein is a fan motor structure including: a shaft; a bearing member coupled to the shaft; a stator coupled to the shaft and disposed at one side of the bearing member; an impeller having a coupling hole and a space part formed therein so as to be in communication with each other, the coupling hole having the bearing member coupled thereto and the space part having the stator received therein; a yoke formed on an inner peripheral surface of the space part; a magnet formed on an inner peripheral surface of the yoke; a diffuser to which an end portion of the shaft is fixed; and a cover coupled to the diffuser and covering the impeller. According to a preferred embodiment of the present invention, a size of the fan motor is decreased.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2012-0070819, filed on Jun. 29, 2012, entitled “Fan Motor Structure”, which is hereby incorporated by reference in its entirety into this application.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a fan motor structure.

2. Description of the Related Art

As an example of a fan motor structure, there may be a fan motor structure applied to a vacuum cleaner. More specifically, the vacuum cleaner, which is a device converting electrical energy into mechanical rotational movement to partially generate vacuum, thereby collect external foreign materials such as dust, or the like, includes the fan motor structure in order to generate the vacuum.

An example of the fan motor structure has been disclosed in Patent Document 1. Patent Document 1 (Korean Patent Registration No. 10-0129217) has disclosed “Motor for Vacuum Cleaner”.

The motor for a vacuum cleaner disclosed in Patent Document 1 is configured by allowing a rotor assembly to be supported by a motor housing having a stator mounted therein and directly coupling a guide vane for forming an efficient channel for sucked air generated and transferred from an impeller and an impeller cover protecting the guide vane and the impeller to each other.

Schematically, in a fan motor structure for a vacuum cleaner according to the prior art including the motor for a vacuum cleaner described above, when external power is applied, electromagnetic force acting between a stator and a rotor is generated to rotate the rotor, such that an impeller installed at an upper end of a shaft of a motor is forcibly rotated, thereby sucking air.

However, the fan motor structure for a vacuum cleaner is a structure in which a motor part including a stator and a rotor is disposed under a fan part including an impeller and an impeller cover and is connected to the fan part, as seen in the motor for a vacuum cleaner disclosed in Patent Document 1.

Therefore, the fan motor structure according to the prior art which is a structure in which the fan part and the motor part are connected to each other in a vertical direction has increased in the entire size. Therefore, a product using the fan motor structure according to the prior art does not satisfy the demand for miniaturization and slimness.

SUMMARY OF THE INVENTION

The present invention has been made in an effort to provide a fan motor structure of which the entire size may be decreased by allowing a motor part to be included in an internal space of a fan part.

According to a preferred embodiment of the present invention, there is provided a fan motor structure including: a shaft; a bearing member coupled to the shaft; a stator coupled to the shaft and disposed at one side of the bearing member; an impeller having a coupling hole and a space part formed therein so as to be in communication with each other, the coupling hole having the bearing member coupled thereto and the space part having the stator received therein; a yoke formed on an inner peripheral surface of the space part; a magnet formed on an inner peripheral surface of the yoke; a diffuser to which an end portion of the shaft is fixed; and a cover coupled to the diffuser and covering the impeller.

Relative rotation of the shaft with respect to the diffuser may not be allowed.

The bearing member may include a bearing including inner and outer races, the inner race may be fixed to the shaft, such that relative rotation thereof with respect to the shaft is not allowed, and the outer race may be coupled to the coupling hole, such that it rotates integrally with the impeller.

The bearing member may include two bearings disposed to be adjacent vertically to each other and including inner and outer races, the inner race may be fixed to the shaft, such that relative rotation thereof with respect to the shaft is not allowed, and the outer race may be coupled to the coupling hole, such that it rotates integrally with the impeller.

The bearing member may further include a bearing housing rotating integrally with the outer race while receiving the two bearings therein, and the impeller may have the bearing housing coupled to the coupling hole thereof while being received in the coupling hole thereof, such that it rotates integrally with the bearing housing.

The bearing member may further include a sealing part formed at one side thereof to cover a gap between an outer peripheral surface of the shaft and an inner peripheral surface of the bearing member.

The space part may be provided with an extension part receiving the yoke and the magnet therein.

The fan motor structure may further include a printed circuit board provided on an upper surface of the diffuser.

The printed circuit board may include a sensing unit sensing a rotational speed of the magnet.

The sensing unit may be a hall sensor.

The bearing member may be press-fitted into the coupling groove.

The shaft may have a low end portion press-fitted into the diffuser.

The cover may be provided with a fitting groove, the diffuser may be provided with a fitting protrusion fitted into the fitting groove, and the cover and the diffuser may be coupled to each other by fitting the fitting protrusion into the fitting groove.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of a fan motor structure according to a preferred embodiment of the present invention;

FIG. 2 is an exploded cross-sectional view of the fan motor structure shown in FIG. 1; and

FIGS. 3 to 5 are cross-sectional views showing various examples of a bearing member shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The objects, features and advantages of the present invention will be more clearly understood from the following detailed description of the preferred embodiments taken in conjunction with the accompanying drawings. Throughout the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant descriptions thereof are omitted. Further, in the following description, the terms “first”, “second”, “one side”, “the other side” and the like are used to differentiate a certain component from other components, but the configuration of such components should not be construed to be limited by the terms. Further, in the description of the present invention, when it is determined that the detailed description of the related art would obscure the gist of the present invention, the description thereof will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a cross-sectional view of a fan motor structure according to a preferred embodiment of the present invention; FIG. 2 is an exploded cross-sectional view of the fan motor structure shown in FIG. 1; and FIGS. 3 to 5 are cross-sectional views showing various examples of a bearing member shown in FIG. 1.

As shown in FIGS. 1 and 2, the fan motor structure 1 according to the preferred embodiment of the present invention is configured to include a shaft 100, a bearing member 200 coupled to the shaft 100, a stator 300 coupled to the shaft 100 and disposed at one side of the bearing member 200, an impeller 400 having a coupling hole 410 and a space part 420 formed therein so as to be in communication with each other, the coupling hole 410 having the bearing member 200 coupled thereto and the space part 420 having the stator 300 received therein, a yoke 500 formed on an inner peripheral surface of the space part 420, a magnet 600 formed on an inner peripheral surface of the yoke 500, a diffuser 700 to which an end portion of the shaft 100 is fixed, and a cover 800 coupled to the diffuser 700 and covering the impeller 400.

The shaft 100 according to the present embodiment 100 has an end portion fixed to a diffuser 700 to be described below, such that rotation thereof is not allowed. In addition, according to the present embodiment, the fan motor structure 1 in which the shaft 100 and an impeller 400 to be described below do not rotates integrally with each other, but the impeller 400 relatively rotates with respect to the shaft 100 is suggested.

More specifically, the shaft 100 has the end portion fixed to the diffuser 700. A central portion of the diffuser 700 may be provided with a fixing hole 701 to which the end portion of the shaft 100 may be fixed. The shaft 100 is fixed to the fixing hole 701 by, for example, a press-fitting method, such that relative rotation of the shaft 100 with respect to the diffuser 700 is not allowed. The shaft 100 vertically stands up upwardly of the diffuser 700 while being fixed to the diffuser 700.

The bearing member 200 is coupled to the shaft 100. The bearing member 200 may include a single bearing 210, as shown in FIG. 3. Alternatively, the bearing member 200 may also include two bearings 210 disposed to be adjacent to each other in a vertical direction, as shown in FIG. 4. Alternatively, although not shown, the bearing member 200 may also include three or more bearings, as needed. Here, in the case in which the bearing member 200 includes two or more bearings, the bearing member 200 may further include a bearing housing 220 receiving two or more bearings 210 therein so that assembling is conveniently performed when the bearing member 200 is coupled to the shaft 100 and a disposition state between the bearings is stably maintained, as shown in FIGS. 1, 2, and 5.

As the above-mentioned bearing 210 configuring the bearing member 200, a general bearing including inner and outer races may be used. Here, the inner race is fixed to the shaft 100, such that rotation thereof is not allowed, similar to the shaft 100. However, relative rotation of the outer race with respect to the shaft 100 is allowed.

In the case in which the bearing member 200 further includes the above-mentioned bearing housing 220, the outer race rotates integrally with the bearing housing 220. That is, relative rotation of the bearing housing 200 with respect to the shaft 100 is allowed.

The stator 300 is coupled to the shaft 100 and is disposed at one side of the bearing member 200. The stator 300 interacts with a magnetic field generated in the magnet 600 when current is applied from the outside to a coil included in the stator 300, thereby generating electromagnetic force. This electromagnetic force acts as rotational force rotating the impeller 400 to which the magnet 600 is fixed.

The impeller 400 receives the above-mentioned bearing member 200 and stator 300 therein. The impeller 400 has the coupling hole 410 and the space part 420 formed therein so as to be in communication with each other in the vertical direction.

The above-mentioned bearing member 200 is coupled to the coupling hole 410 of the impeller 400 while being received in the coupling hole 410. More specifically, in the case in which the bearing member 200 includes a single bearing 210 as shown in FIG. 3, the outer race of the bearing 210 is fixed to the coupling hole 410 by a fixing method such as a press-fitting method, or the like. In this case, the outer race of the bearing 210 and the impeller 400 rotate integrally with each other.

In the case in which the bearing member 200 includes two bearings 210 disposed at upper and lower portions as shown in FIG. 4, the two bearings 210 are coupled to the coupling hole 410 at upper and lower portions of the coupling hole 410 while being received in the coupling hole 410. The outer race of each of the two bearings 210 rotates integrally with the impeller 400, as in the example shown in FIG. 3.

In the case in which the bearing member 200 further includes the bearing housing 200 as shown in FIGS. 1, 2, and 5, the bearing housing 200 is coupled to the coupling hole 410 of the impeller 400 while being received in the coupling hole 410. In this case, the bearing housing 220 rotates integrally with the impeller 400.

The impeller 400 includes the space part 420 formed at one side of the coupling hole 410. The space part 420 provides a space in which the above-mentioned stator 300 is received. Therefore, the impeller 400 receives all of the bearing member 200, the stator, and a region of the shaft 100 to which the bearing member 200 and the stator 300 are coupled therein.

The space part 420 has the yoke 500 fixed to the inner peripheral surface thereof In addition, the yoke 500 has the magnet 600 fixed to the inner peripheral surface thereof and generating the magnetic field. The yoke 500, the magnet 600, and the impeller 400 are configured as one body to form a rotor in the fan motor structure 1 according to the present embodiment.

Meanwhile, the space part 420 may be further provided with an extension part 421, as shown in FIGS. 1 and 2. The above-mentioned yoke 500 and magnet 600 may be fixed so as to protrude in a direction from the inner peripheral surface of the space part 420 toward the center thereof. However, the extension part 421 in which the yoke 500 and the magnet 600 are received and to which the yoke 500 and the magnet 600 are fixed is formed, thereby making it possible to improve convenience in assembling the yoke 500 and the magnet 600 to the impeller 400.

The impeller 400 includes a plurality of blades 401 formed at an outer side thereof so as to suck air from the outside while rotating. The blade 401 may have a spiral shape so as to easily suck the air.

Meanwhile, one side of the bearing member 200 may be provided with a sealing part 201. The sealing part 201 covers a gap between an outer peripheral surface of the shaft 100 and an inner peripheral surface of the bearing member 200 to prevent foreign materials, or the like, from being introduced through the gap.

An upper side of the diffuser 700 may be provided with a printed circuit board 710 for controlling the rotation of the above-mentioned rotor. In addition, the printed circuit board 710 may be provided with a sensing unit for sensing a rotational space of the magnet 600. As a specific example of the sensing unit, a hall sensor 711 may be used.

The hub 700 includes the cover 800 coupled to the upper side thereof. The cover 800 is coupled to the upper side of the diffuser 700 to receive the above-mentioned components including the impeller 400 provided at the upper side of the diffuser 700 therein. In addition, the cover 800 may include an air inlet formed at the upper side thereof so that the air may be sucked by the impeller 400.

In order for the cover 800 to be coupled to the diffuser 700, the cover 800 may be provided with a fitting groove 801 and the diffuser 700 may be provided with a fitting protrusion 702. Further, the cover 800 and the diffuser 700 may be coupled to each other by fitting the fitting protrusion 702 into the fitting groove 801.

In the fan motor structure 1 according to the present embodiment, as described above, the components of the motor including the stator 300 and the magnet 600 are received in the impeller 400, thereby making it possible to decrease a size of the fan motor.

As set forth, according to the preferred embodiment of the present invention, all of the stator, the yoke, the magnet, and the shaft configuring the motor part are received in the impeller, thereby making it possible to significantly decrease the entire size of the fan motor. In addition, inertia of the rotor is minimized, thereby making it possible to rotate the impeller at a high speed.

Although the embodiments of the present invention have been disclosed for illustrative purposes, it will be appreciated that the present invention is not limited thereto, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention.

Accordingly, any and all modifications, variations or equivalent arrangements should be considered to be within the scope of the invention, and the detailed scope of the invention will be disclosed by the accompanying claims. 

What is claimed is:
 1. A fan motor structure comprising: a shaft; a bearing member coupled to the shaft; a stator coupled to the shaft and disposed at one side of the bearing member; an impeller having a coupling hole and a space part formed therein so as to be in communication with each other, the coupling hole having the bearing member coupled thereto and the space part having the stator received therein; a yoke formed on an inner peripheral surface of the space part; a magnet formed on an inner peripheral surface of the yoke; a diffuser to which an end portion of the shaft is fixed; and a cover coupled to the diffuser and covering the impeller.
 2. The fan motor structure as set forth in claim 1, wherein relative rotation of the shaft with respect to the diffuser is not allowed.
 3. The fan motor structure as set forth in claim 1, wherein the bearing member includes a bearing including inner and outer races, the inner race is fixed to the shaft, such that relative rotation thereof with respect to the shaft is not allowed, and the outer race is coupled to the coupling hole, such that it rotates integrally with the impeller.
 4. The fan motor structure as set forth in claim 1, wherein the bearing member includes two bearings disposed to be adjacent vertically to each other and including inner and outer races, the inner race is fixed to the shaft, such that relative rotation thereof with respect to the shaft is not allowed, and the outer race is coupled to the coupling hole, such that it rotates integrally with the impeller.
 5. The fan motor structure as set forth in claim 4, wherein the bearing member further includes a bearing housing rotating integrally with the outer race while receiving the two bearings therein, and the impeller has the bearing housing coupled to the coupling hole thereof while being received in the coupling hole thereof, such that it rotates integrally with the bearing housing.
 6. The fan motor structure as set forth in claim 1, wherein the bearing member further includes a sealing part formed at one side thereof to cover a gap between an outer peripheral surface of the shaft and an inner peripheral surface of the bearing member.
 7. The fan motor structure as set forth in claim 1, wherein the space part is provided with an extension part receiving the yoke and the magnet therein.
 8. The fan motor structure as set forth in claim 1, further comprising a printed circuit board provided on an upper surface of the diffuser.
 9. The fan motor structure as set forth in claim 8, wherein the printed circuit board includes a sensing unit sensing a rotational speed of the magnet.
 10. The fan motor structure as set forth in claim 9, wherein the sensing unit is a hall sensor.
 11. The fan motor structure as set forth in claim 1, wherein the bearing member is press-fitted into the coupling groove.
 12. The fan motor structure as set forth in claim 1, wherein the shaft has a low end portion press-fitted into the diffuser.
 13. The fan motor structure as set forth in claim 1, wherein the cover is provided with a fitting groove, the diffuser is provided with a fitting protrusion fitted into the fitting groove, and the cover and the diffuser are coupled to each other by fitting the fitting protrusion into the fitting groove. 